JPH05247B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a display device for a vehicle, and more particularly to an outside temperature display device for a vehicle suitable for detecting the temperature of the outside air of a vehicle and displaying the detection result.

[Prior art]

Conventionally, this type of outside temperature display device employs an outside temperature sensor installed in a part of the vehicle at a position forward of the rear end of the main body of the internal combustion engine mounted on the vehicle. There is a device that detects the temperature of the outside air at the location where the sensor is installed.

[Problem to be solved by the invention]

However, in such a configuration, even if the outside air temperature sensor is installed at a location where it is unlikely to receive direct sunlight, outside airflow, etc., the outside air sensor receives heat radiated from the internal combustion engine body, and the actual outside air The temperature of the outside air may not be detected correctly, and the temperature of the outside air may be incorrectly displayed. Moreover, such a problem is particularly serious when the internal combustion engine is operating when the vehicle is stopped or running at low speed because the heat radiated from it is difficult to be absorbed by the outside airflow generated by the running of the vehicle.

In order to cope with this problem, the present invention provides an outside temperature display device for a vehicle in which the outside temperature sensor is disposed in a part of the vehicle at a position forward of the rear end of the main body of the internal combustion engine. However, if the outside temperature sensor is predicted to be in a state where it is likely to be affected by the engine body, the display is not updated.

[Means to solve the problem]

In order to solve this problem, the structural feature of the present invention is that, as illustrated in FIG. an outside temperature detection means 1 that detects the temperature of outside air and generates an outside temperature detection signal;
a calculation means 2 for calculating the temperature of the outside air according to the value of the outside air temperature detection signal and generating this as a display output signal; and displaying the value of the display output signal as the temperature of the outside air in response to the display output signal. In the outside temperature display device, the cooling water temperature detection means 4 detects the temperature of the cooling water in the cooling system of the internal combustion engine and generates a cooling water temperature detection signal.
and a traveling speed detecting means 5 which detects the traveling speed of the vehicle and generates a traveling speed detection signal, and the value of the cooling water temperature detection signal is larger than a predetermined temperature value determined in relation to the warm-up end temperature of the internal combustion engine. a discriminating means 6 for generating a discriminating signal when the value of the traveling speed detection signal is smaller than a predetermined low speed value; and a discriminating means 6 for generating a discriminating signal when the value of the traveling speed detection signal is smaller than a predetermined low speed value, and maintaining the generation of the display output signal from the calculating means immediately before the generation of this signal in response to the discriminating signal. This is because a holding means 7 is provided.

[Effect]

By configuring the present invention in this manner, the outside temperature detection means 1 is disposed at a position forward of the rear end of the main body of the internal combustion engine, so that the outside temperature detection means 1 is Even if the engine is susceptible to heat radiation, if the temperature of the cooling water in the cooling system of the internal combustion engine is higher than the predetermined temperature value in relation to the heat radiation of the internal combustion engine, and the running speed of the vehicle is lower than the predetermined low speed value, the determination is made. The means 6 generates a discrimination signal in cooperation with the cooling water temperature detection means 4 and the running speed detection means 5, and in conjunction with this, the calculation means 2, in cooperation with the holding means 7, generates a discrimination signal immediately before the generation of the discrimination signal. Since the display output signal is generated and maintained as it is, and the display means 3 continues to display the display content as it is based on the display output signal, the internal combustion engine may Even if the outside air temperature detecting means 1 cannot correctly detect the temperature of the outside air due to the influence of the heat radiation because the heat radiation is difficult to absorb, the display contents of the display means 3 can display the actual temperature of the outside air almost correctly. .

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 2 shows an example of an outside temperature display device according to the present invention applied to a vehicle, and this outside temperature display device includes an outside temperature sensor 10a. , a microcomputer 30 connected to a cooling water temperature sensor 10b and a running speed sensor 10c, and each A-D converter 20a, 20b and waveform shaper 20c connected to each of these sensors 10a, 10b, and 10c, respectively,
A drive circuit 40 connected to this microcomputer 30 and a display 5 connected to this drive circuit 40.
0.

The outside air temperature sensor 10a is disposed in a part of the vehicle at a position in front of the rear end of the main body of the internal combustion engine mounted on the vehicle, at a position where it is not easily exposed to outside airflow and direct sunlight. However, this outside temperature sensor 1
0a is the temperature of the outside air near the installation position
Ta is detected and an analog outside temperature detection signal is generated at the corresponding level. Cooling water temperature sensor 10
b detects the temperature Tw of the cooling water in the cooling system of the internal combustion engine and generates an analog cooling water temperature detection signal at a level corresponding to this. The traveling speed sensor 10c detects the traveling speed Vs of the vehicle and generates a series of pulse signals at a frequency proportional to this.

The A/D converter 20a digitally converts the level of the analog outside temperature detection signal from the outside temperature sensor 10a, and generates this digital conversion value (hereinafter referred to as digital outside temperature value Ta) as a digital outside temperature signal. The A-D converter 20b digitally converts the level of the analog coolant temperature detection signal from the coolant temperature sensor 10b, and generates this digital conversion value (hereinafter referred to as digital coolant temperature value Tw) as a digital coolant temperature signal. The waveform shaper 20c sequentially shapes each pulse signal from the sensor 10c to generate a shaped signal. The microcomputer 30 executes a display control program stored in advance in the display control program in accordance with the flowchart shown in FIG.
0b and the waveform shaper 20c, and during the repetition of the execution, various arithmetic operations necessary for controlling the drive circuit 40 connected to the display 50 are performed as described below.

In this embodiment configured as described above, when the vehicle is operated by operating its ignition switch to start its internal combustion engine and put it into a running state, and also put the microcomputer 30 into operation, the microcomputer 30 is activated. According to the flowchart of FIG. 3, execution of the display control program is started in step 60, and in step 61, the vehicle is driven based on a series of shaping signals generated by the waveform shaper 20c in cooperation with the traveling speed sensor 10c. Calculate speed Vs. If the warm-up of the internal combustion engine has not been completed at this stage, the microcomputer 30 controls the A-D converter 2 at step 62.
Based on the fact that the value Tw of the digital water temperature signal generated by cooperation with the cooling water temperature sensor 10b from 0b is smaller than the predetermined digital temperature value Two, it is determined as "NO", and in step 65, the digital water temperature signal is output from the A-D converter 20a. Based on the value of the digital outside temperature signal generated in cooperation with the temperature sensor 10a, the outside air temperature Ta is calculated and generated as a display output signal. However, the predetermined digital temperature value Two is stored in advance in the microcomputer 30 as a value corresponding to a temperature of the cooling water that is somewhat lower than the warm-up end temperature of the internal combustion engine.

When a display output signal is generated from the microcomputer 30 as described above, the drive circuit 40 generates the value of the display output signal as a drive signal, and in response, the display 50 outputs the value of the drive signal, that is, the value of the outside air. Displays temperature Ta. In this case, since the internal combustion engine has not yet been warmed up, the amount of heat radiated from the main body of the internal combustion engine is negligible. Therefore, the outside air temperature sensor 10a correctly detects the temperature of the outside air of the vehicle without being affected by heat radiation from the main body of the internal combustion engine, so that the actual outside air temperature can be determined based on the display contents of the display 50. Ta can be recognized correctly.

After that, when the internal combustion engine is warmed up, A-D
Value of digital cooling water temperature signal from converter 20b
When Tw becomes more than the predetermined digital temperature value Two,
The microcomputer 30 determines "YES" in step 62. If the latest calculated running speed Vs at step 61 is equal to or higher than the predetermined low speed value Vso, the microcomputer 30 determines "YES" at step 63, and generates a display output signal at step 65 in the same manner as described above. do. However, the predetermined low speed value Vso is selected as a value that can sufficiently absorb the heat radiated from the main body of the internal combustion engine at the end of warm-up by the outside air flow that occurs when Vs≧Vso, and is set in the microcomputer 30 in advance. remembered.

When a display output signal is generated from the microcomputer 30 as described above, the drive circuit 40 generates the value of the display output signal as a drive signal, and in response, the display 50 outputs the value of the drive signal, that is, the value of the outside air. Displays temperature Ta. In such a case, although the internal combustion engine radiates heat from its main body at a high temperature after warming up, this radiated energy is
≧Vso will be absorbed by the outside airflow generated by the vehicle running. Therefore, the outside temperature sensor 10a correctly detects the temperature of the outside air of the vehicle without being influenced by the main body of the internal combustion engine, so the outside air temperature Ta can be correctly recognized based on the display content of the display 50. It is possible.

In such a state, if the determination in step 63 becomes "NO" due to a decrease in the traveling speed of the vehicle, the microcomputer 30, in step 66, outputs the display output in step 65 immediately before the determination in step 63 as "NO". Keep the signal intact. As a result, the display device 50 is connected to the drive circuit 40.
In cooperation with , the display contents immediately before the "NO" determination in step 63 are continuously displayed thereafter. In such a case, the outside temperature sensor 10a
Even if it is not possible to correctly detect the actual temperature Ta of the outside air due to the high-temperature heat radiated from the internal combustion engine body at the end of warm-up when Vs<Vso,
The display content of the display 50 is based on this outside temperature sensor 10.
Regardless of the erroneous detection of a, in order to maintain the value corresponding to the proper detection result of the outside air temperature sensor 10a immediately before this erroneous detection, the incorrect outside air temperature is recognized from the display content of the display 50. That's not the case.

[Brief explanation of drawings]

FIG. 1 is a diagram corresponding to the configuration of the invention described in the claims, FIG. 2 is a block diagram showing an embodiment of the invention, and FIG. 3 is a flowchart showing the operation of the microcomputer shown in FIG. It's a chat. Explanation of symbols, 10a...Outside temperature sensor, 10b
...Cooling water temperature sensor, 10c...Outside temperature sensor,
20a, 20b...A-D converter, 20c...Traveling speed sensor, 30...Microcomputer,
40...Drive circuit, 50...Display device.

Claims (1)

[Claims] 1. Outside temperature detection means disposed in a part of the vehicle at a position forward of the rear end of the internal combustion engine mounted on the vehicle to detect the temperature of outside air and generate an outside temperature detection signal, and the outside temperature detection signal. and a display means for displaying the value of the display output signal as the temperature of the outside air in response to the display output signal. In the outside temperature display device, the cooling water temperature detection means detects the temperature of the cooling water in the cooling system of the internal combustion engine and generates a cooling water temperature detection signal, and the driving speed detects the running speed of the vehicle and generates the running speed detection signal. a detection means; and a determination that generates a determination signal when the value of the cooling water temperature detection signal is greater than a predetermined temperature value determined in relation to the warm-up end temperature of the internal combustion engine and the value of the traveling speed detection signal is smaller than a predetermined low speed value. An outside temperature display device for a vehicle, characterized in that it is provided with a holding means for maintaining the generation of the display output signal from the calculation means immediately before generation of the signal in response to the discrimination signal.